[T] 3x1 keys

A project log for Tetent [gd0090]

A wireless input device that's slower than... thinking(?) but faster than any other character input method, theoretically.

kelvinAkelvinA 08/10/2022 at 12:410 Comments

I was scanning through my options for the #Tetent Turntable [gd0038] and came to the acceptance that 2 axis joystics were never really going to work that well anyway. It's much harder to move my fingers left/right than up/down, and a rotation axis would have to share a zoom axis. I started thinking about a 1 axis solution, and since the thumb keys are simpler now, it's plausible to press a button to switch between controlling translational and rotational axes. I'm thinking of setting the shift key to switch from translation -> free rotation -> 45 degree step rotation.

I started looking on the internet for "1 axis joysticks" and "spring loaded potentiometers" but it didn't bring up any favourable results. The bigger question was where these joysticks were even going to go. I'm still trying to mine a solution that merges Tetent and Turntable into a BetterTM Tetent, but the entire movement bounding area for the side fingers is used for the keyboard. 

Hmm... the only solution is to integrate the joystick into the keys, but there's not enough space for that. Each key is under 6mm in the Y axis. What about a tracking surface like on blackberries? They're capacitive so won't work with even 1mm long fingernails, and again the available surface are is sub 6mm. Plus, if I could track that, I wouldn't even need 5 seperate keys per column anyway.

Assuming I can get an accurate finger position (with nails and skin), this opens up possibilities. 

  1. I'd only need 1/5 the magnets and hall effect sensors. 
  2. My fingers would be able to easily slide to the next chord without potentially getting caught in the middle gap.
  3. There would be enough space to put the adjustment screws under the keys instead of adding an additional 8mm to the length.
  4. Less magnet force and length means that I can remove the 2mm dowel from the design, potentially reducing the key height.
  5. Would likely look better and more minimalist.
  6. The #Tetent Tiny [gd0040] can get Turntable functionality.
  7. Tetent can be larger whilst fitting in the available space in #Teti since Turntable is no longer needed.
  8. The screen could tell me where my fingers are or the keyboard can send unique pulses to a haptic vibration motor for each of the 5 zones.
  9. The 5 zones would be software adjustable instead of fixed to a 6mm grid.

Now I'm looking for a way to detect distance from 0 - 30mm with milimetre accuracy.